Policy Statement. Objective. Context. References and Supporting Documentation. Policy Statement

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1 Policy Statement Subject Guidelines for Placement of Power Poles Within Road Reserves in Built-Up Areas Approved by Robert Rogerson Signature & Date Distribution Standards and Policy Manager Authorised by Mark Wilshusen Manager Signature & Date Standards, Policy & Data Quality Issue Date 14 August 2006 Issue Initial Objective To position poles in built-up areas so that they comply with regulations and suit Western Power s purposes while minimising inconvenience to other users of the road reserve. Context Road reserves are used by many, and power poles need to be positioned so they cause the least possible inconvenience to other utility providers, property owners and the public, while being of maximum benefit to Western Power. The placement of power poles is regulated through the Utility Providers Code of Practice. The Code applies to both urban and rural or regional road reserves, particularly urban and townsite areas (Section 3.1). However, the requirements defined in the Code need to be expanded upon hence this more detailed policy. References and Supporting Documentation - Main Roads website Utility Providers Code of Practice ENA C(b)1 2006, Guidelines for design and maintenance of overhead distribution and transmission lines. Policy titled: Placement of poles along roads with speed limit not exceeding 70km/h. Policy Statement Power poles should be installed on a standard alignment, between 2.4m and 3m from property boundaries, as defined in Appendix B of the Utility Providers Code of Practice (the Code). However, poles installed on this alignment must also comply with policy titled: Placement of poles along roads with speed limit not exceeding 70km/h. Poles may be installed on other alignments, provided that an agreement in writing is obtained from any utility providers affected by the proposed location (see Sections 3.2 and 8.2 of the Code). Policy Statement 1

2 Poles should also be located in positions that avoid existing entrances to properties and other obstacles and provide for future development (see Section 8.2 of the Code). As well as meeting the requirements of the Code, poles should be installed according to the following guidelines. Guidelines 1) Maximum number of customer services: in order to minimise costs, poles should be positioned so as to maximise the number of customers serviced from one pole. 2) Street lighting: distribution poles are used to carry streetlights. Therefore, they should be positioned to take into account street lighting design requirements. 3) Future extensions: In order to minimise future costs, consideration should be given to the likelihood/possibility of extensions to the existing/proposed distribution network (for example requirements for tee-offs, ground/aerial stays etc). See Figure 1. Figure 1: Consideration of future requirements 4) Customer service poles: consideration should also be given to any advantage that may be achieved by positioning poles on the side of a street that will minimise the number of customer service poles required when service connections are run across the road, as shown in Figure 2. 5) Vegetation clearing: it is important to minimise the impact Western Power s assets have on the environment. Therefore, consideration should be given to positioning poles on the side of the road that will minimise the need for vegetation-clearing, as shown in Figure 2. Policy Statement 2

3 Figure 2: The advantage of careful pole positioning 6) Deviation stays: stays can restrict land use and obstruct pedestrian traffic. Therefore, conductor deviation angles should be avoided or installed in a way that eliminates or reduces the need for deviation stays. If an overhead deviation angle is unavoidable, then adopt the following decision-making process to select the most appropriate option: If the deviation bay length is shorter than 35 metres, use an inline stay for the main conductor and low tension (slack) for the deviation bay, without installing deviation stays. If the deviation bay is longer than 35m, carry out an evaluation of the ground conditions and determine the suitability of a stronger pole. This is to ensure that corner poles will not be moved because of conductor tension, resulting in unacceptable conductor sag across the road. If the deviation bay is longer than 35m and it cannot be constructed without deviation stays, deviation stays may be installed, provided they will not obstruct pedestrian traffic, access to property and will not become a visual obstruction (see Section 16 of this policy). Use an underground option if deviation stays are necessary but cannot be installed without breaching the guidelines in c) above. Policy Statement 3

4 Figure 3: Deviation angles 7) No conductors inside property: in built-up areas it is not acceptable for new overhead power lines to be located inside property boundaries. Figure 4: No conductors inside properties 8) Compliance with ENA C(b)1, Section 9: bare overhead power lines can be built only on the 2.7m alignment in areas zoned for a building setbacks of 6m, or in areas with a special dispensation setbacks of 3m. If zoning allows properties to be built along the front property boundary, bare overhead line construction should not be used. This type of construction in these circumstances would not satisfy the requirements of ENA C(b)1, Section 9, as shown in Figure 5 below. The distance between a building and the closest conductor Policy Statement 4

5 could be reduced to 1.3m as a result of blowout caused by strong wind. The required minimum clearance from the wall is 1.5m and from the window it is 2.1m. Figure 5 Compliance with ENA C(b)1 9) Stays across driveways: stays should not bridge existing or potential driveways. Aerial stays are best avoided and should be used only after all other options have been exhausted. Figure 6: Location of stay poles Policy Statement 5

6 10) HV Earthing a) HV earthing (e.g. earthing for conductive HV poles, pole-top-switches or pole mounted transformers) should not be located within 15m of telecommunication assets. This is because the telecommunication asset could be damaged, or there could be a safety hazard during their maintenance because of the voltage difference between local and remote earths. This includes telecommunication jointing pits, pillars, manholes, and telephone cabinets. b) If an HV earth is to be located within 15m of any telecommunication assets (other then cables), then Telstra (or other relevant communication utility) must be notified and their written approval obtained. b) Poles supporting pole-top-switches should not be located close to existing or proposed driveways and access ways, to avoid damage to the earthing mat during driveway construction. There should be a minimum distance of 2m between the driveway and a pole. Figure 7: Positioning of earthed poles Policy Statement 6

7 11) Driveway crossovers: poles and stays should not be located within 1m of an existing or planned driveway crossover. Figure 8: Poles near driveway crossovers 12) Common lot boundary projection: poles and stays should normally be located at the projection of a common lot boundary. However, where lots are truncated (eg. battleaxe lots) poles should be positioned on or outside the truncation projection. Figure 9: Location of poles on common lot boundaries Policy Statement 7

8 13) Proximity to underground services: poles should not be located in positions that prevent or inhibit access to underground services (e.g. underground power cables, road crossing conduits, gas pipelines, telephone cables or water pipes). Also, adjacent underground services may be damaged during the pole installation process. Figure 10: Proximity to underground services 14) Road Intersections: Poles near intersections should be installed at least 1 mete away from the roadway, as specified in policy number titled, Placement of poles along roads with speed limit not exceeding 70km/h. It is necessary to discuss the placement of these poles with local government staff before finalising designs. Poles should not be installed in the vicinity of an intersection area if they will need to be relocated due to planned intersection upgrading work. Policy Statement 8

9 15) Easements: poles and stays should not be located within the projection of sewerage, drainage and gas pipe easements existing on a property. Figure 12: Poles within easements 16) Visual obstruction: it is important to install overhead assets so that they do not become a visual obstruction. Nor should they become significant landmarks. For example, the following situations have generated customer complaints: LV ABC conductors installed across a view of the lake; and a pole-top transformer installed above surrounding houses and trees, obstructing the view of properties on higher ground some distance away. Policy Statement 9